Connector

ABSTRACT

A connector for making solderless electrical contact between corresponding conductors of bonded wire-pairs each having two parallel conductors.

United States Patent Inventors Dennis J Enright;

James H. Bazille, Jr., St. Paul, Minn. Appl, No. 777,714 Filed Nov. 21,1968 Patented Apr. 6, 1971 Assignee Minnesota Mining and ManufacturingCompany St. Paul, Minn.

CONNECTOR 4 Claims, 6 Drawing Figs. I

11.8. C1 339/98, 339/101, 339/113 Int. Cl H01r 11/20 Field of Search339/97- [56] References Cited UNITED STATES PATENTS 2,097,426 11/1937Arthur et a1. 339/97 2,857,583 10/1958 Mark1eyeta1..... 339/1983,150,910 9/1964 Dodd 339/198 3,162,501 12/1964 Mahl 339/98 FORElGNPATENTS 392,174 5/1933 Great Britain 339/99 192,890 11/1964 Sweden339/99 Primary ExaminerErnest R. Purser Assistant Examiner-Joseph H.McGlynn Attorney-Kinney, Alexander, Sell, Steldt & Delahunt ABSTRACT: Aconnector for making solderless electrical contact between correspondingconductors of bonded wirepairs each having two parallel conductors.

CONNECTOR This invention relates to solderless wire connectors which,although useful in connecting single wires, are particularly adapted foruse with bonded pairs of insulated wires (twinned wires or wire pairs)wherein the two conductors are held. in separated side-by-side parallelrelationship by means of a unitary plastic insulating cover surroundingboth wires and having a figure 8 or twin-circle cross section such as iscommercially available under the trade designation Unipair conductor.These wire pairs come in various wire sizes, e.g. from No. 28 to No. 22B & S gauge, and ordinarily with a polyethylene or similar plasticinsulating covering.

Connectors for flat multiwire cables have previously been described, forexample in U.S. Pat. No. 3,189,863, in which a permanent solderlessconnection is made possible through the use of thin flat resilientbifurcate contact elements which penetrate and displace the plasticinsulating cover and make resilient permanent contact with the conductorwhich is held between the two opposingjaw members.

The present invention similarly employs resilient bifurcate contactelements but in addition includes provision for orienting the wire pairin position to assure the desired interconnection and for separating thewires prior and subsequent to contact with the contact element. Theinvention thereby makes possible the splicing together of correspondingconductors of the several-wire pairs in a minimum of time, to produce afully insulated connection.

In the drawing, which illustrates one preferred embodiment of theinvention:

FIG. 1 is a view in perspective of the assembled connector;

FIG. 2 is a top plan view of the jacket member, with a portion cut awayto show detail;

FIG. 3 is a bottom plan view of the cap member;

FIG. 4 is a sectional elevation taken approximately along the section4-4 of FIG. 3;

FIG. 5 is a sectional elevation taken approximately along the section5-5 of FIG. 2; and

FIG. 6 is a front elevation of the connector as applied to two wirepairs.

The connector 10 of FIG. 1 comprises an open-top cuplike jacket member11 and a cap member 12 fitting therein. An extended front 13 on thejacket 11 is provided with entry ports or channels 14, 15 to receive thetwo wire pairs which are to be interconnected. Indicia suchas the marks16 may be supplied adjacent the entry ports, for example by printing,embossing, molding, or by covering with a decal, to indicate thedisposition of the wire-connecting structure within the connector.Typical dimensions for a connector and useful in connecting two wirepairs having wire sizes of No. 22 to No. 26' or No. 28 gauge may beapproximately 0.58 inch in length, 0.52 inch in width, 0.33 inch inheight in the open condition shown in FIG. I and compressing to 0.24inch in height when applied to the wire pairs as shown in- FIG. 6. Thebase and top are constructed of resiliently rigid polymeric insulatingmaterial, a preferred material being Lexan polycarbonate resin. A cleartransparent resin may be used, thereby permitting a view of thecompleted connection, or the resin may e.g. be pigmented with coloredpowders, or blended with flame retardants, or otherwise modified. A highdegree of rigidity is desired, but suflicient resiliency is required topermit snap closing of the connector body.

The jacket 11 is shown in FIGS. 2 and 5 to be in the shape of anopen-topped rectangular cup, the extension 13 forming a handle. Thebottom of the cup is deeply longitudinally grooved between the end wallsto provide grooves 17, 18 and transversely slotted to providediscontinuous slots 19, 20. Elongate recesses 21, 22 are providedadjacent the sidewalls for a purpose to be described and additionalcavities are provided wherever suitable, for reducing the thickness ofthe section and thus to help in preventing shrink marking;

Extending along the bottom of the cup or jacket I I from the bottomsurfaces ofthe wire channels 14, I5 are rounded wiresupporting surfaces25, 26, 27, 28. The inner surfaces are separated by a central barrierwall 29; the inner and outer surfaces are separated by the grooves 17,18. The transverse slots 19, are of the same depth as the grooves, asshown in FIG. 5, and extend in each instance from one groove to the ad-5 jacent elongate recess and from the other groove to and partly throughthe central barrier wall.

The twin circle wire channels 14, 15 flare outwardly to providewire-accepting flared openings 31, 32. The two circular openings of thewire channels are separated by lower ridges 33, 34 and opposing upperridges 35, 36. The space between upper and lower ridges is justsufficient to permit entry of the connecting web of a wire pair, the twoinsulated wires then fitting within the circularly cross-sectionedportions of the wire channels. FIG. 6 illustrates the position of a setof wire pairs 37,38 in the channels 14, 15 respectively.

The inner surfaces of the walls of the jacket 11 are slightly flaredinwardly to a broken peripheral peak line 39 of minimum diameter,thereby providing for a snap fit with the cap 12.

The cap 12 in FIG. 3 is seen inverted from its normal position atopjacket 11 as shown in FIG. 1. The thus exposed inner surface is providedwith sharp-edged ridges 41, 42 which fit snugly between the end wallsand within grooves l7, 18 respectively of jacket 11. Transversely of theridges are located contact members 43, 44, the member 43 being furthershown in FIG. 4. Each contact member consists of two resilient doublypointed slotted or bifurcate contact elements 45, 46 joined by aconnecting bridge 47 which is embedded in the plastic cap and is firmlyretained by the sharp projecting corners 48, 49. The slots 50, 51 ofcontact member 43 are aligned with the position of the wire ends on thewire-supporting surfaces 25, 27 when the cap is placed on the jacket 11.Similar considerations hold for contact member 44.

Elongate ridges 54, 55 extend outwardly from the side edges of the cap,and analogous extensions may if desired be. provided centrally of theend edges. All four edges of the cap are slightly flared outwardly toform a broken peripheral peak line 56 of maximum diameter. In the openposition shown in FIG. I, the ridges 54, 55 fit below the peak line 39ofjacket I1 and retain the cap against accidental displacement. The endsof the ridges 41, 42 fit against the end walls of the cap to furtherstabilize the connector in the open position.

In making a connection, the two wire pairs 37, 38 are thrust endwiseinto the wire channels l4, 15, which action tends to remove any minorcurvatures in the wire ends. The wire pairs are further guided by theedges of the ridges 41, 42 centered between the sharp longitudinal edgesof the wire-supporting surfaces 25-26 and 27-28 respectively. When thewire pairs are fully inserted, the cap is forced into the closedposition, with its top flush with the edges of the cuplike jacket asseen in FIG. 6. The closing operation is conveniently performed withconventional parallel jaw hand-operated pliers. The sharpedged ridges41, 42 cut through the plastic central connecting web of the wire pairs,forcing the individual insulated conductors into position on theirrespective wire-supporting surfaces. The upturned sharp edges of thewire-supporting; surfaces deflect the separated wires into theirintended positions. The bifurcate contact elements then further centerthe wires, penetrate and displace the insulation, and make permanentresilient contact with the conductor. The ridge 56 snaps past the ridge39 only on application of force sufficient to assure proper separationof the wires and application of the contact elements. The ridges 54,55are received in the recesses 21', 22 respectively. The ridges 41, 42 andthe wall 29 serve to isolate the several wires and to assure thatelectrical flashover between unconnected wires is prevented.

It will be apparent that the structure may be laterallyv extended toaccommodate additional wire pairs the individual conductors of which maythen be connected in any desired order or combination. Anothermodification involves lowering of the end walls and removal of the upperhalf of the extension 13 in alignment with one or more of the wire pairpositions, thereby permitting one or more of the wire pairs to beinserted in the connector at a location intermediate the ends of thewire pair, i.e. to produce a tap or bridged connection. In suchconfiguration the wall segments and the upper portion of the frontextension may be incorporated in the cap structure so that the abilityof the connector to completely contain the connection area may bepreserved. in a further modification a wire-receiving extension may beplaced at each end so that wires or wire pairs may be introduced fromopposite directions; and various other structural modifications andcombinations may be made. Partially filling the connector with aninsulating waterproof paste, e.g. silicone grease, prior to assemblyrenders the final connection water resistant without in any waydecreasing the effectiveness of the electrical connections.

An incidental advantage of the structure illustrated in FIGS. 25 is thatthe 'cap 12 is symmetrical and may be placed with either end toward thewire-entry end of the cup 11. The extended sidearms 54, 55 retain thecap firmly in the open position, and the structure is further stabilizedby contact between the ends of the sharp-edged separators 41, 42 and theend walls of the cup. There is provided an easily assembled,wellstabilized connector with which permanent safe connections betweenwires or wire pairs may easily and quickly be made.

We claim:

l. A wire connector adapted for connecting together corresponding wiresof at least two twinned-wire wire pairs, comprising in combination:

a cup-shaped jacket member havlng a series of generally parallelelongate wire-supporting surfaces, one for each wire of each twinnedpair of wires, ridged to form a continuous ridge between adjacent pairsof wire-supporting surfaces, deeply grooved to form an open groovebetween the two wire-supporting surfaces for each said pair, and slottedtransversely of said grooves to form aligned slots across correspondingwire-supporting surfaces of adjacent pairs;

said cup-shaped member being further provided, for each of said adjacentpairs of wire-supporting surfaces, with access openings alignedtherewith and having an interconnected double circle cross section; and

a cap member, forcefully insertable within said jacket, carryingextended parallel sharp-edged separator plates in line with said groovesand electrically conductive resilient flat thin contact elements in linewith and extending along said aligned slots, each said element beingslotted in line with one set of said corresponding wire-supportingsurfaces.

2. A wire connector as defined in claim 1 wherein said cap is stablysupported on said jacket with said separator plates aligned with saidopen grooves and adjacent said wire-supporting surfaces for guiding wirepairs into position for interconnection.

3. A wire connector as defined in claim 2 and having a wireentryextension containing wire-receiving channels forming said accessopenings in alignment with said wire-supporting surfaces.

4. A wire connector as defined in claim 3 and wherein said wire-entryextension carries indicia for indicating the position of said contactelements.

1. A wire connector adapted for connecting together corresponding wiresof at least two twinned-wire wire pairs, comprising in combination: acup-shaped jacket member havIng a series of generally parallel elongatewire-supporting surfaces, one for each wire of each twinned pair ofwires, ridged to form a continuous ridge between adjacent pairs ofwire-supporting surfaces, deeply grooved to form an open groove betweenthe two wire-supporting surfaces for each said pair, and slottedtransversely of said grooves to form aligned slots across correspondingwiresupporting surfaces of adjacent pairs; said cup-shaped member beingfurther provided, for each of said adjacent pairs of wire-supportingsurfaces, with access openings aligned therewith and having aninterconnected double circle cross section; and a cap member, forcefullyinsertable within said jacket, carrying extended parallel sharp-edgedseparator plates in line with said grooves and electrically conductiveresilient flat thin contact elements in line with and extending alongsaid aligned slots, each said element being slotted in line with one setof said corresponding wire-supporting surfaces.
 2. A wire connector asdefined in claim 1 wherein said cap is stably supported on said jacketwith said separator plates aligned with saiD open grooves and adjacentsaid wire-supporting surfaces for guiding wire pairs into position forinterconnection.
 3. A wire connector as defined in claim 2 and having awire-entry extension containing wire-receiving channels forming saidaccess openings in alignment with said wire-supporting surfaces.
 4. Awire connector as defined in claim 3 and wherein said wire-entryextension carries indicia for indicating the position of said contactelements.